Water is a multi purpose life resource. It uses for drinking, cleaning, irrigation, swimming, and for very wide variety of industrial utilities including in the food industry. Due to the vitality of water for life, population development significantly influenced from the availability of water, and thus efforts are always made to increase water availability and to reduce the expenses involved in their production. This is because the existence of rich water sources not always assures their adaptation to the intended use, due to the presence of other substances in it. In many of water uses there exist standards and health requirements as for the quality of water with respect to the concentration of contaminants in it, which are no doubt essential, but normally increase the production costs of water due to special treatments it should have in order to bringing it with conformity with such standards and requirements. The costs of water treatment is often such high, such that pure populations cannot withstand, thus abandon themselves to the dangers hiding in non treated water. Furthermore, costs of water treatment many time prevent water recycling, and thus even in places all over the world were water is not so much available or low priced, water is wasted in huge amounts after single use, since their recycling treatment costs higher.
Although in pure populations the costs of water production are critical to people lives, they are also of highly significance in well developed populations as well, from several aspects. This is because water treatment costs very much influence life level indexes, since water is involved in all life aspects either directly (i.e. in direct consumption such as drinking, washing, swimming) and indirectly (i.e. in indirect consumption such as industrial processes).
The present invention shall concentrate on disinfection and decontamination of water from health damaging biological and chemical substances.
When dealing with water disinfection, it should always be remembered that in order to maintain the aseptic conditions of disinfected water, it is required that all the solids and gasses that may become in contact with such water should be disinfected as well then maintained in an appropriate aseptic condition.
During the years several basic concepts of disinfection and decontamination of water have been developed, which compete on the global market with their advantages and disadvantages.
Many times, producers harness several disinfection concepts on one production line, wherein, for example, water reservoirs and conveyor belts are decontaminated using toxic chemicals (then washed very strictly to avoid chemical residuals from the end product), water pipes are decontaminated by delivering boiled water, end product bottles are disinfected using chemicals, and the water itself (as a product) may be irradiated by UV light for disinfection.
It is appreciated that a most significant factor in determining what treatment concept would be chosen for a decontamination treatment, is the cost involved. Probably, chemical disinfection process which involves the use of toxic substances which should then be cleaned off and removed, will not be chosen unless other concepts, e.g. heating, costs higher.
Another clean disinfection concept which involves no toxic substances is irradiating the disinfected medium by germicidal UV light. However, although many patents have been issued and many efforts are all the time made to provide UV disinfection system having industrial capacity that may address all sorts of production requirements and still offer reasonable prices either for establishment and for current maintenance, a great success in that field could not yet be observed.
One obstacle in the path of providing optimal UV disinfection devices is the cost of the optics. Optic systems which will allow for a reliable disinfection process needs to ensure that each and every portion of the disinfectant will receive appropriate amount of germicidal energy. Unfortunately, the either the basic costs and the maintenance costs of such optical systems are not small enough so as one may absolutely prefer the UV concept versus others.
One obstacle in the path of providing optimal UV disinfection devices is the cost of the UV light source itself, and of course its maintenance costs.
U.S. Pat. No. 6,454,937 to Horton et. al. and U.S. Pat. No. 5,200,156 to Wedekamp, are both directed to irradiating flowing fluids with UV light in a direction along the flowing path, in order to maximize the efficiency of the UV energy and to minimize the absorption of UV light by the walls of vessels or pipes which contain the irradiated fluid. For this purpose UV light sources are arranged according to said patents to emit maximum energy in a direction parallel to the axis of a pipe (or pipes) through which flows the fluid.